Pedal-operated lawn mowers are known.
A first set of pedal-operated lawn mowers have a frame that includes a steerable front wheel. A mower assembly trails the front wheel. See for example Porath, U.S. Pat. No. 4,455,816 and Chun, U.S. Pat. No. 4,341,058. The front wheel compresses down a strip of uncut grass prior to cutting, resulting in a strip of uncut or poorly cut grass being left behind. The lawn mower can also slide and be difficult to turn in wet grass due to turning forces being generated by a single wheel.
Woodling, U.S. Pat. No. 5,388,393 discloses a pedal-operated lawn mower in which the mower assembly is attached to the front forks of a conventional bicycle whose front tire has been removed. The resulting lawn mower eliminates the problem of uncut grass but turning causes the mower assembly to urge tipping of the bicycle frame to one side. Furthermore, conventional bicycles that would be adapted for use cannot operate in reverse, making it impossible for the lawn mower to back out from under trees or bushes.
Chun further teaches that a pedal-operated lawn mower can also be used as a stationary exercise bike, an advantageous feature. However when the lawn mower disclosed in Chun is used as a stationary exercise bike, pedaling causes the cutting blades to also turn. This poses a safety hazard.
Thus there is a need for an improved pedal-operated lawn mower that can also be adapted for use as a stationary exercise bike. The improved lawn mower should cut the grass without leaving strips of uncut grass, should be stable in turns without the frame being urged to tip, and when used as a stationary exercise bike the mower cutting blades should remain stationary.